116 LABOKATORY OUTLINE OP NEUROLOGY 



and one to the brain stem along the line of contact between the 

 corpus striatum and thalamus (the tcenia chorioidea). Be- 

 tween these two lines the membrane is folded into the ventricle, 

 thus forming the fissura chorioidea. See the references cited in 

 Section 130. 



Now repeat on the human the directions outlined for the 

 sheep in Sections 128 and 129. 



143. Stria terminalis. The human brain, following the pro- 

 cedure outlined in Section 132, may be further dissected as 

 follows : 



Look into the lateral ventricle, as already exposed, and locate 

 the head of the caudate nucleus in the floor of the lateral ven- 

 tricle above the anterior commissure. Now trace the tail 

 (cauda) of the caudate nucleus backward into the inferior horn 

 of the lateral ventricle where it ends in the vicinity of the nu- 

 cleus amygdalae. Also follow the stria terminalis (stria or 

 tsenia semicircularis), which accompanies the ventral border 

 of the caudate nucleus for its entire length. Some of its fibers 

 can be seen to enter the anterior commissure. This stria is 

 a correlation tract between the nucleus amygdalae and the me- 

 dial olfactory area of the same and the opposite side. It 

 marks the boundary between the cerebral hemisphere and the 

 thalamus. 



144. Corpus striatum. Remove the hippocampus. Now 

 pull upward on the corpus callosum and upper wall of the 

 lateral ventricle so as to rip off the entire roof of the ventricle, 

 tearing it free from the upper (lateral) border of the caudate 

 nucleus. The lentiform nucleus (Herrick ('18), Fig. 45) will 

 now be visible on the lateral aspect of the specimen, perhaps 

 still covered superficially by the fibers of the external capsule. 



145. Internal capsule. The broken ends of the internal 

 capsule fibers will now be seen between the caudate nucleus 

 and the lentiform nucleus of the corpus striatum and between 

 the lentiform nucleus and the thalamus. Examine carefully 

 the relations of the internal capsule to the three gray masses. 

 See the list of references at the end of Section 139. 



146. Nucleus anterior thalami. Locate the anterior nu- 

 cleus of the thalamus (also called nucleus dorsalis) which forms 

 a well-defined eminence at the anterior end of the dorsal aspect 



